An automotive bodywork seal generally has the following functions:                that of being retained on its support, which is made up of a bodywork element, this retention function generally being afforded by a rigid part made of a U-section clamp or of a base that is flat overall having openings for the passage of intermediate clips or cramps for fixing to the support;        that of providing, via a “slippery” surface, sealed contact between this support and a fixed light or drop glass or some other part of the bodywork (for example between a door panel and a sliding window in the case of an inner or outer wiping gasket or between a door frame and a side of the bodyshell in the case of a “frame” seal), this sealed contact generally being achieved by a zone of flexible material on which there is an antifriction covering very often consisting of flock; and        that of having, on its or each of its visible face(s) an embellishment covering with a surface that is pleasing to the eye and in harmony with the surrounding components and is also durable, not losing its pleasing appearance with the passage of time.        
This antifriction covering is currently the result either of an “online” application of adhesive followed by flocking (generally made of polyamide or polyethersulfone), or the laminating-on of a flocked strip, these two methods being able to be performed:                in the case of extruded seals, online during the extrusion process, or        in the case of molded seals, afterwards during an additional operation that follows a multi-shot injection molding of each seal.        
As far as the embellishment covering is concerned this may be obtained either in the form of a film by laminating it onto an extruded seal or by painting, for example, or by adding an add-on trim molding in order to give the seal the desired appearance.
One major disadvantage with applying these coverings or laminating them onto the profile sections, both online and as an additional operation afterwards, lies in the general need to activate the support beforehand in order to make the adhesive or the strip stick. In addition, it is often found that the post-production cutting operation using punch and die that is generally performed to finish the extruded strip, in addition to carrying an additional cost, may cause the strip to begin to detach, this detachment being worsened by the fairly intensive daily use made of the seal once it is mounted on the vehicle (e.g. sliding, vibration, hand contact in particular).
Another disadvantage inherent to the in-line application methods is that the extrusion that has to be used in such cases does not allow the creation of a component of non-constant section nor does it allow the “hidden” (i.e. inaccessible) zones of a profile section to be treated with antifriction surfaces or surfaces of heightened appearance, and in addition does not allow the simultaneous treatment on the one hand of the longitudinal face of the profile section that is to be provided with an antifriction covering or the one that is to be provided with an embellishment film and, on the other hand, the rounded or angular end edge faces of this profile section.
As for the existing two-shot injection molding methods, these have the disadvantage of it not being possible to plan for simultaneous use of several strips or films, or for the covering of the end edge faces of the profile sections. The problem is that the inserts hitherto applied to the bottom of the two-shot injection molds cover only the relevant (near-planar or curved) longitudinal face of the profile section, carrying the following major risks in the case of the antifriction covering or embellishment covering that this inset provides, which may prove to be:                either too short, leaving part of the fair face the appearance of which was to be heightened by the insert visible, or alternatively leaving uncovered a functional part which, in the case of an antifriction covering, will have too high a coefficient of friction and will cause the treated zone to malfunction, for example by causing the lip of the weatherstrip to curl over, or by causing the glass that is supposed to slide in it to judder, etc.;        or too long, with the insert forming added thickness or folding over and causing incorrect operation of the functional part that it covers or difficulties with assembly (e.g. clogging) or alternatively protruding unattractively beyond the ends of the profile section, necessitating an additional trimming operation afterwards.        